# 方法1
a = 10
i = 1
while i < 5:
    a += 2
    i += 1

print(a)

# 方法2
a = 10
b = [i for i in (2, 2, 2, 2)]
b.append(a)
print(sum(b))

# 方法3
def nian(n):
    if n == 2:
        return 10
    else:
        return nian(n-1) + 2
    
print(nian(6))